PR feedback (Mihai): More explicit comment on DirectoryPattern

src/Shared/FileMatcher.cs

@@ -796,7 +796,9 @@ bool needsRecursion
             public string Filespec { get; }
             /// <summary>
             /// Holds the directory pattern for globs like **/{pattern}/**, i.e. when we're looking for a matching directory name
-            /// regardless of where on the path it is.
+            /// regardless of where on the path it is. This field is used only if the wildcard directory part has this shape. In
+            /// other cases such as **/{pattern1}/**/{pattern2}/**, we don't use this optimization and instead rely on
+            /// <see cref="RegexFileMatch"/> to test if a file path matches the glob or not.
             /// </summary>
             public string DirectoryPattern { get; }
             /// <summary>